A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Greg Rudzinski
Date: 2015 Apr 22, 17:18 -0700
I thought it would be fun to do trials comparing various sextants using a water pool artificial horizon vs. a Bendix MK 5 bubble octant. 20 observations of the Sun were made with each sextant (Tamaya Jupiter, Cassen & Plath, and M.Low US Navy MK 3). The same Tamaya 4x40mm scope was used on all three sextants. 40 observations of the Sun, Venus, Polaris, and Sirius were made with the Bendix MK 5 bubble octant which is equiped with a 2x scope. Conditions were ideal for all observations with winds at or below 8 knots. All three sextants performed well with only 4 of the 60 LOP intercepts falling outside of 1'. The Bendix MK 5 did well also with just a single LOP of 40 falling outside of 4'.
For traditionalists traveling by vehicle off road in a desert the bubble octant will be good enough requiring only short stops to grab observations. If traveling a river by boat, kayak, or canoe then the added accuracy of a water pool artificial horizon would be the better bet to prevent transiting down the wrong tributary.